CNG-powered Chevy Sonic, Cruze headed your way | Covert Ford Chevrolet Hutto

The value proposition for a Crazy Diamond Performance CNG ride was a little bit better before gas prices took a dive in the past month. Still, the Michigan-based company, which converts some of Chevrolet's compact vehicles to run on compressed natural gas, received approval late last month from the US Environmental Protection Agency (EPA) for two of its conversion models. And CNG is still pretty cheap.

Crazy Diamond will start selling CNG versions of both the Chevrolet Cruze and Chevrolet Sonic. The startup will target fleet operators looking to cut both refueling costs and their carbon footprint. CNG can be found in much of the country in the low $2 range, while the average CO2 emissions are about 25 percent less than those of similar gas-powered vehicles. Average gas prices have tumbled by more than 30 cents a gallon in the last month, according to AAA, but they're still at close to $3.

The two models will be able to go almost 300 miles on a full tank of CNG. Crazy Diamond said this summer that it would start selling converted a CNG-powered Cruze that delivers 130 horsepower for as low as $26,000. The turbocharged version goes for about $28,000.